replace 'virtual ... OVERRIDE' with '... override'

base/threading/thread.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_THREADING_THREAD_H_
 #define BASE_THREADING_THREAD_H_
 
 #include <string>
 
 #include "base/base_export.h"
@@ skipping 183 matching lines @@
  private:
 #if defined(OS_WIN)
   enum ComStatus {
     NONE,
     STA,
     MTA,
   };
 #endif
 
   // PlatformThread::Delegate methods:
-  virtual void ThreadMain() OVERRIDE;
+  void ThreadMain() override;
 
 #if defined(OS_WIN)
   // Whether this thread needs to initialize COM, and if so, in what mode.
   ComStatus com_status_;
 #endif
 
   // Whether we successfully started the thread.
   bool started_;
 
   // If true, we're in the middle of stopping, and shouldn't access
@@ skipping 21 matching lines @@
   std::string name_;
 
   friend void ThreadQuitHelper();
 
   DISALLOW_COPY_AND_ASSIGN(Thread);
 };
 
 }  // namespace base
 
 #endif  // BASE_THREADING_THREAD_H_